In the handling of articles which are transported from one area to another it is necessary to deposit and pick up the articles or loads. A typical situation is when articles or loads are removed from a conveyor such as a roller conveyor and transferred to a spaced location. One common system utilized is separate forklift trucks or similar devices. Such devices are not applicable to automatic storage and retrieval systems wherein accuracy is required in positioning the load to a close tolerance for pick up by an automatic device such as a computer controlled crane. Another system that has been used is to utilize a transfer car that carries a piece of the conveyor that acts both as a transporting conveyor when the car is in position adjacent the conveyor and as a carrier for holding the article or load when the car is moving to a remote station. In such a system, since the car leaves the transportation conveyor, a gap is created interrupting the flow of loads or articles.
Accordingly, among the objects of the invention are to provide a system wherein a transfer car has interdigitating capability with a transportation conveyor or a pick up station; which leaves no conveyor gap permitting continuous operation; wherein there is no external control source required; wherein only one drive is required for all functions of moving the car and transferring the load between the conveyor and a remote station; and wherein the system may be adapted to either pick up at a conveyor and deposit at a station or the reverse, namely, pick up at a station and deposit on a conveyor.